Building-stand for condensers



B. MACPHERSON.

BUILDING STAND FOR CONDENSERS.

APPLICATION FILED NOV. 19. 1919.

1 83 7246, Patented Apr. 20, 1920.

-4. d (D Z4 /4 AT /(7 T UNITED STATES PATENT oEEIoE.

BYRON MACPHERSON, OEROXBUBY, MASSACHUSETTS, ASSIGNOR, BI MESNE ASSIGN- MENTS, 'I O MICA CONDENSER COMPANY, LTD, OF BOSTON, MASSACHUSETTS, A COR- PORATION OF MASSACHUSETTS.

BUILDING-STAND FOB GONDENSERS.

Specification of Letters Patent.

Patented Apr. 20, 1920.

To all whom it may concern:

Be it known that I, BYRON MACPHIERSON, a citizen of the United States, and resident of Roxbury, in the county of Suffolk and State of Massachusetts, have invented an Improvement in Building- Stands for Condensers, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

My present invention relates to electrical condensers and more particularly to improved building frames or stands for manufacturing the same.

In my copending application, Ser. No. 339,242, filed Nov. 19, 1919, I have described and claimed an improved process and apparatus for coating mica plates with varnish or other suitable insulating material to provide a surface thereon which will enable me to obtain intimate engagement of the foil and the mica as well as to seal any minute perforations that may exist in the mica sheet. In carrying out my improved method of manufacturing electrical condensers, described and claimed in my coending application, Ser. No. 339,241, filed ov. 19, 1919, I use the treatedmica sheets above referred to as the dielectric between the sheets of foil. To effect economy in manufacture and to insure that each pile is correctly assembled, I have devised the building frame or stand which is the subj ect of the present application. To assemble such elements, with the assurance that each sheet of foil is individually tested for short circuits and for position in the stack during such assembling, has resulted'in the total elimination of throw-outs formerly necessary because of poor mica put into the stack and because of improper assemblin The object of my invention therefore, is an improved building frame or stand for electrical condensers of the sheet or plate type.

In the accompanying drawings showing the preferred embodiment of my invention, Figure 1 is a plan view of the frame or stem Fig. 2 is a side elevation; and

Fig. 3 is a plan view of asheet of mica.

On any suitable block or bench 10, I arrange spaced blocks 11 and 12 of conducting material, such as brass or the like. Near of the blocks 11 and 12 and substantially midway the length thereof are pins 17 and 13 respectively. Fitting on the blocks :11

and 12 between the pins 15, 13 and 17 is a block 25 of insulating material, such as fiber or the like. Pins 16 and 14 passing through the insulating block 25 and into the blocks 11 and 12 respectively, of conducting material, are so spaced with respect to the pins 15, 17 and 13 as to correctly center a sheet of mica 20 shown in Fig. 3, in a frame. I have also shown pins 18 and 19 on the opposite side of the bench 10 and occupying the same relative position as the pins 16 and 14, but such pins 18 and 19 are not essential, and may be dispensed with. It is to be understood, of course, that the pins 13, 14, 16, 17, 18 and 19, and also, for convenience, the pin 15, are made of conducting material, such as brass.

At 23 I have designated a source of power, connected one end to the conducting plate 11 and the other end, through an indicating device 24, to the conducting plate 12. While the source of p ower 23 is shown as a battery, and the indicating device is conventionally illustrated, it is to be understood that I may employ any type of low potential current source, and any type of visual or audible signal device. For safety to the operator, I preferably employ a source of power 23 that delivers current of not over 20 volts pressure, but it is possible, of course, to utilize current of either lower or higher voltage.

In building a condenser stack. I lay a mica sheet 20 on the insulating plate25, this sheet being properly spaced and retained in position by the pins 19, 14, 15, 16 and 18. *On this mica sheet 20 I place a sheet of foil 21, this being properly spaced and retained in position, as the stack is shown built in Fig. 2, by the pins 19, 13 and 14. Another mica sheet 20 is placed in position on the foil sheet 21 and then a second foil sheet placed in position, being properly spaced and retained in position by the pins 18, 17 and 16. Should any. of the mica sheets employed have a perforation large enough to allow the electrical engagement of the foil sheets on either side thereof, a circuit will be com pleted from battery 23, indicating device 24;, conducting block 12, pins 13, 14 and (or) 19, to one sheet of foil, thence to the other sheet of foil, at the point of contact through the perforation in the mica sheet, thence to the pins 16, 17 and (or) 18, and back to the battery. The operator, by seeing the indication on the signal device 24 if such signal is a visible one, or by hearing the signal if an audible one, is apprised of the fact that a more careful scrutiny and possible rejection of an interposed mica sheet is necessary, It sometimes happens that an opera tor places two sheets of foil incorrectly in position, but forgets or neglects to interpose the necessary sheet of mica. She is immediately apprised of such fact by the completion of the circuit through the indicating device in substantially the manner above described. Except intentionally therefore, it is impossible to build a stack with defective insulating material, or to incorrectly assemble the various stack elements.

While I have shown the preferred embodiment of my invention, it is to be understood that I may vary the size, shape, and arrangement of elements shown within reasonably wide limits without departing from the spirit of the invention.

My invention is further described and defined in the form of claims as follows:

1. An improved building stand for electrical condensers and the like, comprising a base, means thereon for correctly spacing and positioning sheets of mica, auxiliary means thereon for correctly spacing and positioning sheets of foil, and alarm means for indicating the presence of defective sheets of mica.

2. An improved building stand for electical condensers and the like, comprising a base, conducting plates spaced apart thereon, conducting pins connected to and extending upwardly from said plates and positioned to properly space and position sheets ofmica and foil, a source of power, and indicating means connected thereto, said source of power and said indicating means being connected to, the conducting plates, said indicating means operating upon the completion of the circuit therethrough due to the contact of adjacent sheets of foil.

3. An improved building stand for electrical condensers and the like, comprising a base, conducting plates spaced apart thereon, conducting pins connected to. said plates and extending upwardly therefrom, a source of power and an indicating device connected to said plates, said indicating means operable upon incorrect assembling of the stack to notify the operator.

In testimonywhereof I have signed my name to this specification in the presence of two subscribin witnesses.

YRON MACPHERSON.

Witnesses:

AUBREY R. GooDwIN, JAMES R. HODDER. 

